This invention relates to high speed programmable prescalers and, in particular, to high speed programmable prescalers that require a minimum count to accomplish a full program.
Very high speed prescalers that perform a divide by 10 or 11 under a mode control and operate within the 650 MHz range are known in the art. An example of these devices is the 11C90 manufactured by Fairchild Semiconductor Components Group of Fairchild Camera and Instrument Corporation. These devices have aroused great interest in VHF and UHF counters for applications in mobile communicational and digitally tuned FM and TV receivers. Although the above mentioned applications differ in many ways, they all have one thing in common; the need for high speed programmable prescalers. The prior art modulo-2 type programmable prescalers have basically two major limitations. One, clocking speeds are limited by critical path delays and two, the minimum count necessary to accomplish a full program is limited.